1. Field of Invention
The invention relates to a power management system for a communication device.
2. Description of Related Art
There are conventional on-board navigation systems, wherein route guidance data is preliminarily transmitted to the on-board navigation system prior to a user's departure and the user is provided with route guidance based on the transmitted route guidance data at his or her departure (please refer to Japanese patent laid-open H6-243395 and H9-189566.) In this conventional system, the user operates a personal computer at home or at work in order to input a destination, a route search criterion, and the like. As a result, a route is searched and route guidance data is transmitted to a navigation apparatus over wireless communication. With such conventional system, the user is provided with the route guidance from the beginning of his or her drive. However, inconveniently, inputting a destination, a route search criterion, and the like; searching the route; and transmitting the data must be carried out while the vehicle is stopped or parked.